Aromatic modified aliphatic hydrocarbon resins have been used in solvent based tape formulations (U.S. Pat. No. 4,250,272, U.S. Pat. No. 5,177,163, WO 91/07472). However, the tape industry has begun lowering coating weights so that new and optimized systems are required to comply with this trend. Lower coating weights decrease the tack properties of the adhesive, and the hydrocarbon resins must therefore be modified to maintain the desired adhesion strength.
U.S. Pat. No. 3,846,352 (Goodyear) discloses the use of cyclic diolefins in combination with 2-methyl-2-butene in the polymerization feed for the production of aliphatic hydrocarbon resins. Further, alpha-methylstyrene was used for aromatic modifications. However, the resin properties were not related to the adhesive behavior, so that no optimization according to the requirements at lower coating weights were carried out.
U.S. Pat. No. 4,104,327 and U.S. Pat. No. 4,636,555 disclose the use of alpha-methylstyrene and para-methylstyrene in the aromatic part of the feed for the production of aromatic modified aliphatic hydrocarbon resins, respectively.
In view of the above, the present invention aims to provide novel aromatic modified aliphatic hydrocarbon resins with excellent tack and shear properties even at low coating weights. It is also an object of the invention to provide a method for the preparation of such aromatic modified aliphatic hydrocarbon resins. A further object of the invention is the use of the aromatic modified aliphatic hydrocarbon resins as mono-tackifiers in solvent based tape formulations. The invention further aims to provide an adhesive tape comprising the aromatic modified aliphatic hydrocarbon resin of the invention.